The short seller Andrew Left's Citron Research has initiated a position against Riot Blockchain.

Shares of Riot Blockchain have soared more than 375% since the company pivoted to blockchain technology from biotech in October.

The shares are now shrugging off the news of Left's short position.

Shares of Riot Blockchain are shrugging off the news that the short seller Andrew Left Citron Research has initiated a position against the company. They're trading up 33.5%, near $38 apiece, on Monday.

"Full mania," Citron's Twitter account said on Monday. "No reason to short any stocks now that even have business while the market has given us stocks like $RIOT. Starting short position here. The bar for finding good shorts has been lowered."

Riot Blockchain is one of many companies that have seen a significant jump in market cap after announcing a pivot to the blockchain space. Over the past week, shares of LongFin Corp. soared as much as 2,400% after announcing it had purchased Ziddu, a blockchain company specializing in business-to-business warehouse payments.

Getting in on blockchain has been a hot trend as of late as companies look to capitalize on the booming cryptocurrency space. Over the weekend, CME Group launched bitcoin futures, sending the cryptocurrency to a record high of nearly $20,000 a coin.

In total, the cryptocurrency universe has a market cap of more than $600 billion, according to CoinMarketCap.com.